VisualFrequencyView.java

package org.zywx.wbpalmstar.plugin.uexaudio;

import java.util.Random;

import org.zywx.wbpalmstar.base.ResoureFinder;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.PixelFormat;
import android.graphics.drawable.Drawable;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.view.View;

public class VisualFrequencyView extends View {

	private static final int WIDTH_COUNT = 12;
	private static final int HEIGHT_COUNT = 12;
	private static final int ACTION_UPDATE_VIEW = 100;
	private int[] list = new int[12];
	private Bitmap blueBlock;
	private Bitmap grayBolck;
	private int blockWidth;
	private int blockHeight;
	private boolean isUpdating = false;
	private Random random = new Random();
	 private ResoureFinder finder = null;
	private Handler handler = new Handler() {
		public void handleMessage(Message msg) {
			if (isUpdating) {
				updateView(getRandomArray());
				handler.sendEmptyMessageDelayed(ACTION_UPDATE_VIEW, 60);
			}
		};
	};

	public VisualFrequencyView(Context context) {
		super(context);
		finder = ResoureFinder.getInstance(context);
		init();
	}

	public VisualFrequencyView(Context context, AttributeSet attrs) {
		super(context, attrs);
		finder = ResoureFinder.getInstance(context);
		init();	
	}

	public VisualFrequencyView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, 0);
		finder = ResoureFinder.getInstance(context);
		init();
	}

	private void init() {
		for (int i = 0; i < 12; i++) {
			list[i] = HEIGHT_COUNT;
		}
		blueBlock = getBitmap(getResources().getDrawable(finder.getDrawableId("plugin_audio_blue_block_shape")));
		grayBolck = getBitmap(getResources().getDrawable(finder.getDrawableId("plugin_audio_gray_block_shape")));
		blockHeight = blueBlock.getHeight();
		blockWidth = blueBlock.getWidth();
	}

	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		final Bitmap localGray = grayBolck;
		final Bitmap localBlue = blueBlock;
		final int w = blockWidth;
		final int h = blockHeight;
		final int[] localList = list;
		for (int i = 0; i < WIDTH_COUNT; i++) {
			final int itemValue = localList[i];
			for (int m = 0; m < HEIGHT_COUNT; m++) {
				if (m >= itemValue) {
					canvas.drawBitmap(localBlue, i * w, m * h, null);
				} else {
					canvas.drawBitmap(localGray, i * w, m * h, null);
				}
			}
		}
	}

	private void updateView(int[] randoms) {
		if (randoms == null || randoms.length != WIDTH_COUNT) {
			return;
		}
		for (int i = 0; i < WIDTH_COUNT; i++) {
			final int itemHeight = randoms[i];
			if (itemHeight > list[i]) {
				list[i] += 2;
			} else if (itemHeight < list[i]) {
				list[i] -= 2;
			}
		}
		invalidate();

	}

	public void startResponse() {
		if (!isUpdating) {
			handler.sendEmptyMessage(ACTION_UPDATE_VIEW);
			isUpdating = true;
		}
	}

	public void stopResponse() {
		handler.removeMessages(ACTION_UPDATE_VIEW);
		isUpdating = false;
		for (int i = 0; i < 12; i++) {
			list[i] = HEIGHT_COUNT;
		}
		invalidate();
	}

	public boolean isUpdatingView() {
		return isUpdating;
	}

	private Bitmap getBitmap(Drawable drawable) {
		Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(),
				drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565);
		Canvas canvas = new Canvas(bitmap);
		canvas.setBitmap(bitmap);
		drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
		drawable.draw(canvas);
		return bitmap;
	}

	private int[] getRandomArray() {
		int[] array = new int[WIDTH_COUNT];
		for (int i = 0, size = array.length; i < size; i++) {
			array[i] = random.nextInt(HEIGHT_COUNT);
		}
		return array;
	}
}